Intro to parasitology

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Parasite = an organism thats dependent metabolically on another, where that organism benefits at the expense of the other

Harm to host

Number

Site

Feeding habits

Blood

Gut contents etc

Competition for nutrients

Cost

Animals

Welfare

Productivity

Prevention

Anthelmintics

Managing prophylactic treatments

Climate change - affects epidemiology, prevalence + distribution

Development occurs on pasture

Doesn't occur = no infection

Often temp dependent

Pathogen types

Virus

Genetic code

Protein-fat coat

Size = 3,569 bp

Bacteria

Unicellular

Prokaryote

Size = 1,800,000 bp

Fungi

Often multicellular

Size = 30,000,000 bp

Parasites

Single-celled eukaryotes

Multicellular eukaryotes

Trematode

Size = 1,300,000,000 bp

Nematodes

Size = 100,000,000 bp

Host-Parasite relationship

Parasites evolved to survive in the host long enough to reproduce

Evade host immune response

Suppress/manipulate host immune response

Host immune system evolved to eliminate invaders but parasites persist

Types of Parasite

Helminths

Nematodes

Platyhelminths

Arthropods

Arachnids

Insects

Protozoa

Single celled organisms

Taxonomy

Kingdom -Animal

Phylum -Nemathelminths

Class -Nematoda

Order -Strongylida

Family -Trichostrongylidae

Genus -Teladorsagia

Species - T. Circumcinta

Nematodes

Roundworms

Cylindrical

Range of sizes

Free living + parasitic

Digestive system

Mouth

Buccal cavity

Oesophagus

Intestine

Anus

Excretory pore - not all

Female > male in size

External decorations

Females have vulval flap

Males have bursa at tail end

Rays

Male spicules involved in inseminating female

Cervical papillae - species identification

Direct lifestyle = one host species involved